SAMA5D35 USB Can't support EHCI

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HELLO, everyone. I'm so puzzled in UPLL Generation.  I'M using SAMA5D35 USB , And Want to use UPLLCK as my USB source clock.

look downside pic, USB CAN Use UPLLCK as a source clock If selected USBS. But when I selected the UPLLCK , I Found It's only 240MHZ!!!!

So I need some tools to check the freq.  I Found the way solute my problem,  the pic below give a information ,  I Can use PCK2 check my UPLLCK. 

But not a surprise , I mean , It's realy only 240MHZ, I choose CSS Selected UPLLCK, and PRES is 16, And my mainck is 12MHZ, so if my UPLLCK is right , it's must be output on PCK2 with

the freq: 12M*40/16 = 30MHZ . but disapointment.

SO The CPU has a bug ? the datasheet means the UPLL Just multiple the mainck 40 times, but only 20 times in fact. 

hey, hello world !

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can anyone meet the same question ? 

hey, hello world !

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You've not really given us much to comment on. Maybe if we could see how you've setup UPLLCLK? Surely there's some example code that sets up the USB peripheral that you can use as an example?

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thanks for your reply . The UPLLCLK just multiple the mainck as 40 times. It's not my configuration, 

the UPLLCK Must be MAINCK*40,  if the MAINCK is 12MHZ, so my UPLLCK would be 480MHZ. but the fact is 240MHZ.

hey, hello world !

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Still not enough evidence. Have you tried contacting your local Atmel FAE?

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Finally, I got the problem solution.  the MCKR register BIT13 must be cleared , even the reference manual  datasheet  not report anything, but experiment compare linux and rtos of mine, the register configuration  between MCKR difference is BIT13. maybe the datasheet not refresh.

 

hey, hello world !